Question

Is it possible to declare ExceptionHandlers in a class and use them in more than one controller, because copy-pasting the exception handlers in every controller would be redundant.

-Class declaring the exception handlers:

@ExceptionHandler(IdentifiersNotMatchingException.class)
@ResponseStatus(HttpStatus.BAD_REQUEST)
def @ResponseBody
String handleIdentifiersNotMatchingException(IdentifiersNotMatchingException e) {
    logger.error("Identifiers Not Matching Error", e)
    return "Identifiers Not Matching Error: " + e.message
}

@ExceptionHandler(ResourceNotFoundException.class)
@ResponseStatus(HttpStatus.NOT_FOUND)
def @ResponseBody
String handleResourceNotFoundException(ResourceNotFoundException e) {
    logger.error("Resource Not Found Error", e)
    return "Resource Not Found Error: " + e.message
}

-ContactController

@Transactional(propagation = Propagation.REQUIRED, rollbackFor = Exception.class)
@RequestMapping(value = "contact/{publicId}", method = RequestMethod.DELETE)
def @ResponseBody
void deleteContact(@PathVariable("publicId") String publicId) throws ResourceNotFoundException, IdentifiersNotMatchingException {...}

-LendingController

@Transactional(propagation = Propagation.REQUIRED, rollbackFor = Exception.class)
@RequestMapping(value = "lending/{publicId}", method = RequestMethod.PUT)
def @ResponseBody
void updateLending(@PathVariable("publicId") String publicId, InputStream is) throws ResourceNotFoundException {...}

Answer 1

One way to do this is to have a base class that your controllers extend (could be abstract). The base class can then hold all of the “common” things, including exception handlers, as well as loading common model data, such as user data.